A nichrome wire is connected to a low-voltage laboratory supply. The power dissipated in the wire is 2.0 W when the current in it is 0.40 A. The resistance of the wire does not change. What current is needed for the power dissipated in the wire to be 4.5 W?
0.36 A0.36\ \mathrm{A}0.36 A
0.60 A0.60\ \mathrm{A}0.60 A
0.27 A0.27\ \mathrm{A}0.27 A
0.90 A0.90\ \mathrm{A}0.90 A
105 exam-style questions on Edexcel GCSE Physics 10.3 Electrical energy and power, covering 10.3.1 The heating effect of an electric current, 10.3.2 Reducing energy transfer in wires, 10.3.3 Advantages and disadvantages of the heating effect, 10.3.4 Energy transferred by an electrical circuit, 10.3.5 Electrical power, and 10.3.6 Energy transfers in domestic devices. Each one has a worked solution and a mark scheme showing where the marks go.